mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-24 07:20:37 +00:00
182 lines
6.8 KiB
EmacsLisp
182 lines
6.8 KiB
EmacsLisp
;;; env.el --- functions to manipulate environment variables
|
|
|
|
;; Copyright (C) 1991, 1994, 2000, 2001, 2003 Free Software Foundation, Inc.
|
|
|
|
;; Maintainer: FSF
|
|
;; Keywords: processes, unix
|
|
|
|
;; This file is part of GNU Emacs.
|
|
|
|
;; GNU Emacs is free software; you can redistribute it and/or modify
|
|
;; it under the terms of the GNU General Public License as published by
|
|
;; the Free Software Foundation; either version 2, or (at your option)
|
|
;; any later version.
|
|
|
|
;; GNU Emacs is distributed in the hope that it will be useful,
|
|
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
;; GNU General Public License for more details.
|
|
|
|
;; You should have received a copy of the GNU General Public License
|
|
;; along with GNU Emacs; see the file COPYING. If not, write to the
|
|
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
;; Boston, MA 02111-1307, USA.
|
|
|
|
;;; Commentary:
|
|
|
|
;; UNIX processes inherit a list of name-to-string associations from their
|
|
;; parents called their `environment'; these are commonly used to control
|
|
;; program options. This package permits you to set environment variables
|
|
;; to be passed to any sub-process run under Emacs.
|
|
|
|
;; Note that the environment string `process-environment' is not
|
|
;; decoded, but the args of `setenv' and `getenv' are normally
|
|
;; multibyte text and get coding conversion.
|
|
|
|
;;; Code:
|
|
|
|
;; History list for environment variable names.
|
|
(defvar read-envvar-name-history nil)
|
|
|
|
(defun read-envvar-name (prompt &optional mustmatch)
|
|
"Read environment variable name, prompting with PROMPT.
|
|
Optional second arg MUSTMATCH, if non-nil, means require existing envvar name.
|
|
If it is also not t, RET does not exit if it does non-null completion."
|
|
(completing-read prompt
|
|
(mapcar (lambda (enventry)
|
|
(list (if enable-multibyte-characters
|
|
(decode-coding-string
|
|
(substring enventry 0
|
|
(string-match "=" enventry))
|
|
locale-coding-system t)
|
|
(substring enventry 0
|
|
(string-match "=" enventry)))))
|
|
process-environment)
|
|
nil mustmatch nil 'read-envvar-name-history))
|
|
|
|
;; History list for VALUE argument to setenv.
|
|
(defvar setenv-history nil)
|
|
|
|
|
|
(defun substitute-env-vars (string)
|
|
"Substitute environment variables referred to in STRING.
|
|
`$FOO' where FOO is an environment variable name means to substitute
|
|
the value of that variable. The variable name should be terminated
|
|
with a character not a letter, digit or underscore; otherwise, enclose
|
|
the entire variable name in braces. Use `$$' to insert a single
|
|
dollar sign."
|
|
(let ((start 0))
|
|
(while (string-match
|
|
(eval-when-compile
|
|
(rx (or (and "$" (submatch (1+ (regexp "[:alnum:]_"))))
|
|
(and "${" (submatch (minimal-match (0+ anything))) "}")
|
|
"$$")))
|
|
string start)
|
|
(cond ((match-beginning 1)
|
|
(let ((value (getenv (match-string 1 string))))
|
|
(setq string (replace-match (or value "") t t string)
|
|
start (+ (match-beginning 0) (length value)))))
|
|
((match-beginning 2)
|
|
(let ((value (getenv (match-string 2 string))))
|
|
(setq string (replace-match (or value "") t t string)
|
|
start (+ (match-beginning 0) (length value)))))
|
|
(t
|
|
(setq string (replace-match "$" t t string)
|
|
start (+ (match-beginning 0) 1)))))
|
|
string))
|
|
|
|
;; Fixme: Should `process-environment' be recoded if LC_CTYPE &c is set?
|
|
|
|
(defun setenv (variable &optional value unset substitute-env-vars)
|
|
"Set the value of the environment variable named VARIABLE to VALUE.
|
|
VARIABLE should be a string. VALUE is optional; if not provided or is
|
|
`nil', the environment variable VARIABLE will be removed. UNSET
|
|
if non-nil means to remove VARIABLE from the environment.
|
|
SUBSTITUTE-ENV-VARS, if non-nil, means to substitute environment
|
|
variables in VALUE with `substitute-env-vars', where see.
|
|
Value is the new value if VARIABLE, or nil if removed from the
|
|
environment.
|
|
|
|
Interactively, a prefix argument means to unset the variable.
|
|
Interactively, the current value (if any) of the variable
|
|
appears at the front of the history list when you type in the new value.
|
|
Interactively, always replace environment variables in the new value.
|
|
|
|
This function works by modifying `process-environment'.
|
|
|
|
As a special case, setting variable `TZ' calls `set-time-zone-rule' as
|
|
a side-effect."
|
|
(interactive
|
|
(if current-prefix-arg
|
|
(list (read-envvar-name "Clear environment variable: " 'exact) nil t)
|
|
(let* ((var (read-envvar-name "Set environment variable: " nil))
|
|
(value (getenv var)))
|
|
(when value
|
|
(push value setenv-history))
|
|
;; Here finally we specify the args to give call setenv with.
|
|
(list var
|
|
(read-from-minibuffer (format "Set %s to value: " var)
|
|
nil nil nil 'setenv-history
|
|
value)
|
|
nil
|
|
t))))
|
|
(if (and (multibyte-string-p variable) locale-coding-system)
|
|
(let ((codings (find-coding-systems-string (concat variable value))))
|
|
(unless (or (eq 'undecided (car codings))
|
|
(memq (coding-system-base locale-coding-system) codings))
|
|
(error "Can't encode `%s=%s' with `locale-coding-system'"
|
|
variable (or value "")))))
|
|
(if unset
|
|
(setq value nil)
|
|
(if substitute-env-vars
|
|
(setq value (substitute-env-vars value))))
|
|
(if (multibyte-string-p variable)
|
|
(setq variable (encode-coding-string variable locale-coding-system)))
|
|
(if (and value (multibyte-string-p value))
|
|
(setq value (encode-coding-string value locale-coding-system)))
|
|
(if (string-match "=" variable)
|
|
(error "Environment variable name `%s' contains `='" variable)
|
|
(let ((pattern (concat "\\`" (regexp-quote (concat variable "="))))
|
|
(case-fold-search nil)
|
|
(scan process-environment)
|
|
found)
|
|
(if (string-equal "TZ" variable)
|
|
(set-time-zone-rule value))
|
|
(while scan
|
|
(cond ((string-match pattern (car scan))
|
|
(setq found t)
|
|
(if (eq nil value)
|
|
(setq process-environment (delq (car scan)
|
|
process-environment))
|
|
(setcar scan (concat variable "=" value)))
|
|
(setq scan nil)))
|
|
(setq scan (cdr scan)))
|
|
(or found
|
|
(if value
|
|
(setq process-environment
|
|
(cons (concat variable "=" value)
|
|
process-environment))))))
|
|
value)
|
|
|
|
(defun getenv (variable)
|
|
"Get the value of environment variable VARIABLE.
|
|
VARIABLE should be a string. Value is nil if VARIABLE is undefined in
|
|
the environment. Otherwise, value is a string.
|
|
|
|
This function consults the variable `process-environment'
|
|
for its value."
|
|
(interactive (list (read-envvar-name "Get environment variable: " t)))
|
|
(let ((value (getenv-internal (if (multibyte-string-p variable)
|
|
(encode-coding-string
|
|
variable locale-coding-system)
|
|
variable))))
|
|
(if (and enable-multibyte-characters value)
|
|
(setq value (decode-coding-string value locale-coding-system)))
|
|
(when (interactive-p)
|
|
(message "%s" (if value value "Not set")))
|
|
value))
|
|
|
|
(provide 'env)
|
|
|
|
;;; env.el ends here
|